In recent years, the prevalence of a recorder capable of simultaneously recording a plurality of programs, a television set with a recording function, a smart phone, a digital camera, a digital video camera, and the like has significantly increased the number of contents held in devices at home, such as a photograph, a moving picture, and a recorded program.
Against this background, a technique has been known which causes a server provided on a network to store and manage contents at home. For example, Patent Document 1 discloses a technique which includes a content management DB that manages information about the whereabouts of a content stored in a delivery server, acquires, upon receipt of the content ID of a content desired to be viewed from a viewer client, the whereabouts information of the content desired to be viewed from the content management DB, and notifies the viewer client of the whereabouts information.
Patent Document 1 also discloses that a control information storage section is caused to store the whereabouts information managed by the content management DB and, when trouble occurs in the content management DB and the acquisition of the whereabouts information of the content desired to be viewed fails, the whereabouts information of the corresponding content is acquired from the control information storage section and given to the viewer client.
However, in the method of Patent Document 1, the contents are collectively stored in the delivery server and no consideration is given to a change in the place where each of the contents has been stored. This leads to the problem that, when the place where a content desired to be viewed has been stored is changed, the real storage place of the content cannot be specified and the content cannot be viewed.
Patent Document 1: Japanese Patent No. 4677992